Okay let me try to explain. You really can't tell if your o day is approaching by looking at your temps. Some women's temps will drop right before they ovulate but this doesn't always happen and it doesn't necessarily mean you will ovulate just because your temp drops. What you should be looking for are fertile signs like you are having more cm particularly ewcm, ovulation cramping, or other signs you are ovulating. You may have your own patterns. For example, I get headaches around the time I ovulate and the time AF is about to show.
What your chart does for you is confirms ovulation. So you can tell when you have ovulated but not until after it happens. Your temp will go up after you ovulate and then you will know that it has happened and can relax with bding and just start staring at your chart.
From looking at your cm and spotting I really think you are going to ovulate soon! Or your body may be trying to anyway.